13 research outputs found
A clinical evaluation of the performance of five commercial artificial intelligence contouring systems for radiotherapy
Purpose/objective(s)Auto-segmentation with artificial intelligence (AI) offers an opportunity to reduce inter- and intra-observer variability in contouring, to improve the quality of contours, as well as to reduce the time taken to conduct this manual task. In this work we benchmark the AI auto-segmentation contours produced by five commercial vendors against a common dataset.Methods and materialsThe organ at risk (OAR) contours generated by five commercial AI auto-segmentation solutions (Mirada (Mir), MVision (MV), Radformation (Rad), RayStation (Ray) and TheraPanacea (Ther)) were compared to manually-drawn expert contours from 20 breast, 20 head and neck, 20 lung and 20 prostate patients. Comparisons were made using geometric similarity metrics including volumetric and surface Dice similarity coefficient (vDSC and sDSC), Hausdorff distance (HD) and Added Path Length (APL). To assess the time saved, the time taken to manually draw the expert contours, as well as the time to correct the AI contours, were recorded.ResultsThere are differences in the number of CT contours offered by each AI auto-segmentation solution at the time of the study (Mir 99; MV 143; Rad 83; Ray 67; Ther 86), with all offering contours of some lymph node levels as well as OARs. Averaged across all structures, the median vDSCs were good for all systems and compared favorably with existing literature: Mir 0.82; MV 0.88; Rad 0.86; Ray 0.87; Ther 0.88. All systems offer substantial time savings, ranging between: breast 14-20 mins; head and neck 74-93 mins; lung 20-26 mins; prostate 35-42 mins. The time saved, averaged across all structures, was similar for all systems: Mir 39.8 mins; MV 43.6 mins; Rad 36.6Â min; Ray 43.2 mins; Ther 45.2 mins.ConclusionsAll five commercial AI auto-segmentation solutions evaluated in this work offer high quality contours in significantly reduced time compared to manual contouring, and could be used to render the radiotherapy workflow more efficient and standardized
Location of submacular hemorrhage as a predictor of visual outcome after intravitreal ranibizumab for age-related macular degeneration
PSMA-PET/CT-guided salvage radiotherapy in recurrent or persistent prostate cancer and PSA < 0.2 ng/ml.
PURPOSE
The purpose of this retrospective, multicenter study was to assess efficacy of PSMA-PET/CT-guided salvage radiotherapy (sRT) in patients with recurrent or persistent PSA after primary surgery and PSA levels < 0.2 ng/ml.
METHODS
The study included patients from a pooled cohort (n = 1223) of 11 centers from 6 countries. Patients with PSA levels > 0.2 ng/ml prior to sRT or without sRT to the prostatic fossa were excluded. The primary study endpoint was biochemical recurrence-free survival (BRFS) and BR was defined as PSA nadir after sRT + 0.2 ng/ml. Cox regression analysis was performed to assess the impact of clinical parameters on BRFS. Recurrence patterns after sRT were analyzed.
RESULTS
The final cohort consisted of 273 patients; 78/273 (28.6%) and 48/273 (17.6%) patients had local or nodal recurrence on PET/CT. The most frequently applied sRT dose to the prostatic fossa was 66-70 Gy (n = 143/273, 52.4%). SRT to pelvic lymphatics was delivered in 87/273 (31.9%) patients and androgen deprivation therapy was given to 36/273 (13.2%) patients. After a median follow-up time of 31.1 months (IQR: 20-44), 60/273 (22%) patients had biochemical recurrence. The 2- and 3-year BRFS was 90.1% and 79.2%, respectively. The presence of seminal vesicle invasion in surgery (p = 0.019) and local recurrences in PET/CT (p = 0.039) had a significant impact on BR in multivariate analysis. In 16 patients, information on recurrence patterns on PSMA-PET/CT after sRT was available and one had recurrent disease inside the RT field.
CONCLUSION
This multicenter analysis suggests that implementation of PSMA-PET/CT imaging for sRT guidance might be of benefit for patients with very low PSA levels after surgery due to promising BRFS rates and a low number of relapses within the sRT field
Changing from bevacizumab to ranibizumab in age-related macular degeneration. Is it safe?
Dimitrios A Karagiannis1, Ioannis D Ladas2, Efstratios Parikakis1, Ilias Georgalas2, Athanasios Kotsolis2, Giorgos Amariotakis1, Vasileios Soumplis1, Panagiotis Mitropoulos11Ophthalmiatrio Eye Hospital of Athens, Athens, Greece; 2First Department of Ophthalmology, Medical School of Athens University, General Hospital of Athens, Athens, GreeceObjective: To report our experiences in changing from intravitreal bevacizumab to ranibizumab in age-related macular degeneration (AMD).Design: Retrospective case series.Participants and methods: We retrospectively reviewed the records of 34 patients (36 eyes) who were treated with monthly injections of intravitreal bevacizumab for six months and then switched to monthly injections of ranibizumab for 12 months. Best-corrected visual acuity measurements (BCVA), contact lens biomicroscopy, optical coherence tomography (OCT), and fluorescein angiography were performed at the baseline examination and then monthly. Chi-square test was used for statistical analysis.Results: Following bevacizumab treatment, retinal thickness decreased (P = 0.033) while BCVA improved (P = 0.040). Changing from bevacizumab to ranibizumab resulted in a transient decrease in BCVA (P = 0.045) and an increase in retinal thickness (P = 0.042). In addition, three eyes presented with a large subretinal hemorrhage. However, final retinal thickness was better than the initial thickness and the value following the bevacizumab course. No major ocular or systemic side effects were noted.Conclusions: Ranibizumab was clinically effective in the long term but the change of treatment from bevacizumab to a half-size molecule with less half-life in the vitreous such as ranibizumab contributed to a transient “instability” in the eye which may have triggered the large subretinal hemorrhage. There is insufficient experience reported in the literature in switching from one agent to another. A prospective study with controls is necessary to determine whether it is safe to change from one medication to another.Keywords: age-related macular degeneration, bevacizumab, ranibizumab, subretinal hemorrhag
Unilateral hypertensive choroidopathy as a sole manifestation in malignant hypertension: optical coherence tomography angiography findings-case report
Abstract Background We present a case of hypertensive choroidopathy due to malignant hypertension with exudative retinal detachment as a sole finding. We use OCT- angiography for initial diagnosis and report findings from extensive follow up. Case presentation A 51-year-old female with no past medical history, presented to our clinic with painless loss of vision in her left eye. Fundus examination revealed only exudative retinal detachment in her left eye that was confirmed with Optical Coherence Tomography. Fluorescein angiography showed hyperfluorescent spots with leakage in late phases. OCTA manifested a focal dark area in the choriocapillaris slab corresponding to flow signal voids, signifying regions of non-perfusion. Her blood pressure was 220/120 mmHG. Complete blood work -up failed to reveal any other possible etiology. During follow-up period of 9Â months blood pressure normalized, patient regained visual function and choriocapillaris perfusion was completely restored. Discussions and conclusions Hypertensive choroidopathy with exudative retinal detachment can be the only sign of malignant hypertension and no pre-existing history of a systemic disease is required in order to become apparent. OCTA reveals areas of non-perfusion at choriocapillaris level, proving that it is an essential tool in the diagnosis and follow up of patients with hypertensive choroidopathy. Finally, we propose that early diagnosis prevents permanent damage of the RPE and leads to complete choroidal remodeling and better visual outcomes
The Effect of Eplerenone in Chronic Central Serous Chorioretinopathy Refractory to Photodynamic Therapy
Acute Zonal Occult Outer Retinopathy with Atypical Findings
Background. To report a case of acute zonal occult outer retinopathy (AZOOR) with atypical electrophysiology findings. Case Presentation. A 23-year-old-female presented with visual acuity deterioration in her right eye accompanied by photopsia bilaterally. Corrected distance visual acuity at presentation was 20/50 in the right eye and 20/20 in the left eye. Fundus examination was unremarkable. Visual field (VF) testing revealed a large scotoma. Pattern and full-field electroretinograms (PERG and ERG) revealed macular involvement associated with generalized retinal dysfunction. Electrooculogram (EOG) light rise and the Arden ratio were within normal limits bilaterally. The patient was diagnosed with AZOOR due to clinical findings, visual field defect, and ERG findings. Conclusion. This is a case of AZOOR with characteristic VF defects and clinical symptoms presenting with atypical EOG findings
Spontaneous Resolution ofLong-Standing Macular Detachment due to Optic Disc Pit with Significant Visual Improvement
Purpose: To report a case of spontaneous resolution of a long-standing serous macular detachment associated with an optic disc pit, leading to significant visual improvement. Case Presentation: A 63-year-old female presented with a 6-month history of blurred vision and micropsia in her left eye. Her best-corrected visual acuity was 6/24 in the left eye, and fundoscopy revealed serous macular detachment associated with optic disc pit, which was confirmed by optical coherence tomography (OCT). The patient was offered vitrectomy as a treatment alternative, but she preferred to be reviewed conservatively. Three years after initial presentation, neither macular detachment nor subretinal fluid was evident in OCT, while the inner segment/outer segment (IS/OS) junction line was intact. Her visual acuity was improved from 6/24 to 6/12 in her left eye, remaining stable at the 6-month follow-up after resolution. Conclusion: We present a case of spontaneous resolution of a long-standing macular detachment associated with an optic disc pit with significant visual improvement, postulating that the integrity of the IS/OS junction line may be a prognostic factor for final visual acuity and suggesting OCT as an indicator of visual prognosis and the probable necessity of a surgical management